Sorry, I reread my reply. So many typo's Should be average 14 days, not 4 days.
Normally your period will not be the same time every month. You have to count the number of days your cycle lasts. The first day of your period is day 1. When your next period starts, you start ounting at 1 again. Write it down if you need to.
Do you know around how long your cycles are? They are normally not exactly the same length every month, but more or less in the range of 26 to 32 days. For a 28 day long cycle, you should have intercourse from about day 10 to day 17 of that cycle. You can have sex daily during that time, or every second day. Both should work just fine.
Your partner should not masturbate during that week, and you should make sure that you use a sperm friendly lube like PreSeed (if you need a personal lubricant). After he orgasmed, lay on your back for a few minutes (10 to 15) with your behind raised on a pillow to keep his semen inside you and close to your cervix. If you have your orgasm a few seconds or up to a minute after him, his sperm will travel quicker to your ovaries (it is not necessary for you to orgasm to conceive).
Your husband should stay away from tight pants and underwear, stay out of hot tubs and jaccuzis. Heat in his genitals makes him less fertile. You should also both reduce alcohol intake while tic.